Valve for internal-combustion engines.



F. McCLlNTOCK.-

VALVE'FOR lNTERNAL COMBUSTION ENGINES. APPLICATION FILED NOV 12, 1913..RENEWED MAR. 2. 1911- v 1,242,460. Patented Oct. 9,1917.

2 SHEETS-SHEET l.

N on NN 3 w w v Q 3 3m ww V h m wn f A H w -m- I w 7 w QN w 3 w w .w m Qv 1 a H N if m b ////////V/// ea mw l MN AX mm v NW W\ Q W \r 0 w 3 NR w9 w/ J Q? Q, m an IV 4 m W////////////// N R WITNESSES:

F. McCLINTOCK. VALVE FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILEDNOV '2' I913 RENEWED M AR. 2, I917.

Patented Oct. 9,1917.

2 SHEETS-SHEET 2- UNITED STATES PATENT OFFICE.

FRANK MOCLINTOC K, F GRAND JUNCTION, COLORADO;

VALVE FOR INTERNAL-COMBUSTION ENGINES.

Application filed November 12, 1913, Serial No. 800,474. Renewed March2, 1917.

To all whom it may concern:

Be it known that I, FRANK MCCLINTOCK, a citizen of the United States,residing at Grand Junction, in the county of Mesa and State of Colorado,have invented certain new and useful Improvements in Valves forInternal-Combustion Engines, of which the following is a specification.

, My invention relates especially to rotary or reciprocating valves forinternal combustion engines which are located external to the combustionchamber of the cylinder, and the objects of my invention are, first, toprovide a valve fitted sufficiently loose within its casing to allow forexpansion by heat without dangerot' sticking or seizing, and providedwith recessed connectingports adapted to connect the combustion chamberwith the intake and exhaust pipes in proper sequence, said connectingports being sealed gas tight when in operative communication with thecombustion chamber; and, second, to provide means for holding the valvegas tight in its seat against the outward pressure of the cylinder gasesduring the compression and power strokes of. the engine piston, suchcounter pressure being automatically varied proportional to that withinthe cylinder; and, third, to provide an antifriction bearing block fordistributing the counter pressure over substantially the entire surfaceof the valve in order to reduce the working pressure and friction andmake the wear uniform over the finished surface of the valve.

I attain these objects by means of the mechanism shown in theaccompanying drawings, in which:

Figure 1 is a vertical cross section view 4 showing the preferredconstruction of a rotary valve embodying my invention; Fig. 2 is alongitudinal section view of the valve, these two figures showing thevalve as designed especially for a two-cylinder internal 5 combustionengine of the four-cycle type; Fig. 3 is a cross section view to showmore clearly the eccentricity of the valve within its casing; Figs. 4and 5 are sectional, views showing alternative forms of construction ofthe mechanism for holding the valve against its seat; Fig. 6 shows analternative arrangement of the ports of the rotary valve. Similarreference characters refer to simi lar parts in each of the severalviews shown.

The rotary valve, shown in Figs. 1 and 2,

Specification of Letters Patent.

Patented Oct. 9, 1917.

Serial No. 152,151.

as the preferred form of construction embodying my invention, consistsof an annular cylinder 6 having a diameter somewhat less than the boreof its cylindrical casing 7. The outer surface of the valve is finishedtruly cylindrical, and is then ground into a longitudinal seat at thatside of the casing where the several port openings are 7 located, thegrinding being continued until such seat extends laterally a suflicientdistance each side of the port openings to insure a gas tight fit of thevalve and its recessed connecting ports during the entire time they arein operativecommunication with the combustion chamber. This constructionis more clearly shown in Fig. 3. in which the original internal bore ofthe casing 7 is shown by the broken lines, while the full lines show thevalve after being ground into its seat. The axis 4: of the valve, whenseated, is thus slightly eccentric to the axis 5 of the casing. Thegrinding of the valve seat to the required width during construction isvery essential, since the pressure of the valve against its seat is sonearly balanced when in operation that the wearing of the valve to aproper seat in the casing during operative rotation could not occur.This construction not only provides ample clearance to allow for theexpansion of the valve by heat, but also allows oil to be appliedanddistributed freely to its surface for lubrication, while the gas tightsealing of the recessed connecing ports prevents leakage of exhaustgases into the valve casingand the consequent heating of the valve andaccumulation of carbon in the casing.

Three port openings, 8, 9 and 10, for each cylinder, are locatedlongitudinally along the valve seat and parallel with the axis of A thecasing as shown in Fig. 2. The central port 9, extends directly into thecombustion chamber 11 of the cylinder and may be termed the cylinderport; the left-hand port 8, provides the inlet for the combustiblecharge, while the right hand port 10, is the outlet for the exhaustgases.

Each valve is provided with two recessed ports, 12 and 13, which areadapted to connect the cylinder port 9, alternately at the proper timeto the inlet port 8, and the exhaust port 10. The angular width of theseveral port openings in the valve casing and the width and angulardistance between the two recessed valve ports 12 and 110 13, should besuch as will give the desired timing of the opening and closing of theinlet and exhaust ports. In Fig. 1 the exhaust port is shown fully open,the engine piston having completed substantially onehalf of the exhauststroke. In Fig. 2, the inlet port of the lefthand valye, is shown fullyopen, the corresponding piston hav ng completed nearly one-half of itsinduction stroke, and the right-hand valve is closed, that piston havingcompleted substantially one-half of its compression stroke. Each sectionof the valve here shown, is provided with only a single recessed inletport and a single recessed exhaust port and is therefore designed tomake one revolution for each four strokes or two revolutions of theengine crank shaft. The valve may be retated at the required rate by anysuitable gearing, such as the link belt chain 14, shown, which connectsthe sprocketwheel 15, to a similar sprocket wheel on the engine crankshaft, having one-half the number of teeth. It will be evident that therelative speed of rotation of the valve may be further reduced byincreasing the number (if the recessed ports therein. F or instance; avalve having two recessed inlet ports located diametrically oppositeeach other and two recessed exhaust ports also located diametricallyopposite each other would be required to make only one revolution forfour revolutions of the engine crank shaft.

In a valve of this type, where the outward pressure of the confinedgases tends to force the valve away from its seat, it is evident thatsome form of counter pressure ,must be provided. In order that the pres-.sure of the valve against its seat may be maintained substantiallyuniform throughout the cycle and be just enough to insure a gas tightfit, this counter pressure must be suflicient in amount to overbalancethe direct outward pressure of the cylinder gases against such area ofthe valve as is exposed thereto, and should vary directly proportionalto the pressure within the cylinder.

The varying pressure of the cylinder gases has heretofore been utilizedto apply this counter pressure to the valve by means of a piston orpressure block having an area somewhat greater than the area of thecylinder port; one side of such piston or pressure block being exposedto the pressure of the cylinder gases and the otherbeing in contact withthe valve. This construction, however, puts an excessively high maximumpressure on a limited area of the highly heated valve causing unequalwear and excessive friction on that part of the valve and makingefficient and uniform lubrication difiicult to maintain.

I overcome these difficulties by providing eta-ace a bearing block,interposed between the pressure block or piston and the valve,

whereby the required counter-pressure may be distributed uniformly oversubstantially the entire effective bearing surface of the valve, thusreducing the pressure per square inch so low that the wear and frictionwill be reduced to a minimum, and uniform. and perfect lubrication maybe easily maintained.

The preferred mechanism for carrying out this essential feature of myinvention comprises the bearing block 16 which is located in a recess inthe valve casing diametrically opposite from the port openings 8, 9 and10. The length of this bearing block should nearly or quite equal thatof the valve and of such maximuin width as is practical. Sincesubstantially the entire pressure load of the valve is carried by thebearing block it should preferably be made of some suitable antifrictionmetal and its inner surface should be closely fitted to the surface ofthe valve.

A pressure block 17, having an area equal to or slightly greater thanthat of the cylinder port 9 is secured to the outer face of the bearingblock 16, or may be made an integral part therewith. The excess in areaof the-pressure block 17 over that of the port 9 should only be suchthat the counter pressure thereon will always hold the valve gas tightin its seat. A frame plate 18, of substantially the same thickness asthe pressure block 17, incloses said pressure block, but is spaced fromdirect contact with the bearing block 16. A flexible gas tight diaphragm19 is placed over. the pressure block and frame plate and is securedthereto by means of the recessed plate 20, which is securely bolted tothe valve casing as shown. The gas tight pressure chamber 21, which isthus formed, is at all times indirect communication with the combustionchamber of the engine cylinder 11, by means of an opening 22, so thatthe pressure within said pressure chamber will at all times besubstantially the same as in the engine cylinder. This pressure, actingthrough the flexible diaphragm 19, on the entire area of the pressureblock 17, in contact therewith is transmitted to substantially theentire outer effective bearing surface of the valve 6, whereby thepressure per square inch is so reduced that efficient lubrication may beeasily maintained and the valve at all times held gas-tight in its seatagainst the outward pressure of the cylinder gases on the area of thevalve exposed through the cylinder port 9. Any desired excess ofpressure above the minimum required for holding the valve in ts seat maybe secured by further increasing the area of the pressure block. Thearea 'of the bearing block 16 being many times greater than that of thepressure block 17,

' its maximum pressure against the valve will in internal combustionengines.

With a valve constructed as shown it will be evident that 'theweight ofthe valve will cause it to drop away from its seat, and it is desirablethat the valve be retained in actual contact with its seat, particularlyduring the induction and exhaust strokes of the engine piston. This maybe effected by a spring 23, located within the pressure chamber 21. Thepressure of this spring on the pressure block need not be suflicient toprevent lubri eating oil from being carried by the valve to its seatduring the low pressure part of the cycle.

In order to prevent excessive heat Within the pressure chamber 21, anopening 24 may be provided, which has a check valve 25, through whichfresh air will be drawn during each induction stroke of the enginepiston. The size of the air inlet openmg 24,

should be limited so as to admit only enough fresh air to scavenge thepressure chamber 21 and opening 22.

In order to allow the required flexibility between the valve drivingshaft 35, and the valve 6, as well as between the several sections ofvalve in multi-cylinder engines, some forms of universal joint, such asthat shown in the drawings, shouldbe provided.

An alternative form of construction of the valve is shown in Fig. 4,wherein the required variable counter pressure to hold the valve gastight in its seat may be secured, by mechanical means only. A steelspring 26, of suflicient tension, has one end permanently secured to thevalve casing at 27. This spring engages a central rib on the outer faceof the pressure block 16. The

free end of the spring 26, is engaged by a horizontally moving slide 28,which has a roller bearing 29. A cam 30, secured to the driving shaft35, engages the roller 29 and is of the proper contour to move the slide28 toward the left, at such a rate and the proper distance to cause thespring 26 to exert a pressure on the bearing block 16,.

which will be substantially proportional to and always sufficiently inexcess of the outward pressure of the confined gases within the cylinderon the valve to hold it gas tight in its seat during the compression andpower It will be,

-e'vident that this form of construction will be best adapted for use onengines where the variations in cylinder pressures aresubstantiallyuniform and constant, as is the case either when an engine is workingunder a constant load, or'when the hit and miss governor is used forspeed and power regulation.

In another form of construction shown in Fig. 5, the presure of thecylinder gases is sure to the bearing block with substantially no lossof pressure, and the'action is practically instantaneous.

Fig. 6 shows a modified design in the ari rangement of the connectingports in the rotary valve, which is adapted for engines of one cylinder.In this valve the inlet and exhaust orts are cut entirely through thevalve wa ls. A cross partition 33 divides the valve and one end admitsthe gaseous charge through a pipe 34, while the exhaust gases may passout through the other open end of the valve.

I have shown a continuously rotating cyllindrical valve as being formany reasons the preferred form of construction, to carry out the.principle of my invention. I do not, however, intend to limit myinvention to any specific type of valve, since it is evident that theprinciple of my invention may be readily adapted for reciprocatingvalves of either fiat or circular section by one skilled in the art.

What I claim as new and by Letters Patent, is: A

1. The combination in an internal combustion engine of a valve casingprovided. with port openings in its seat, a valve adapted to open andclose the port openings in desire to secure proper sequence, a pressurechamber hav ing a. somewhat greater area than the cylinder port in opencommunication with the combustion chamber, a flexible gas tightdiaphragm and a bearing'block having an outer part corresponding insection with and extending into the pressure chamber to a contact withthe entire exposed area of the diaphragm and an inner surface many timesgreater in area than the pressure chamber and closely fitted tosubstantially the entire outer effective bearing surface of the valve. 7

2. The combination in an internal combustion engine of a cylindricalvalve casing provided with port openings in its seat, a cylindricalvalve adapted to open and close the port openings in propersequence, apressure chamber having a somewhat greater area than the cylinder portin open communication with the combustion chamber,

a flexible gas tight diaphragm, and a bearpressure chamber to contactwith the entire exposed area of the diaphragm and an inner surface manytimes greater in area than the pressure chamber and closely fitted tosubstantially the entire effective outer bearing surface of the valve.

3. The combination in an internal combustion engine of a valve casingprovided with port openings in its seat, a valve adapted to open andclose the port openings in proper sequence, a bearing block'closelyfitted to substantially the entire effective outer bearing surface ofthe valve, a spring engaging the outer face of said bearing block andmeans for applying a variable pressure to said spring which will besuflicient to hold the valve gas tight in its seat at all times.

4. The combination in an internal combustion engine of a valve casingprovided with port openings in its seat, a valve adapted to open andclose the port openings in proper sequence, a bearing block closelyfitted to substantially the entire effective outer bearing surface ofthe valve, a spring engaging the outer face of said bearing block, .asliding arm engaging the free end of said spring, and a cam secured tothe valve driving shaft and of such shape as will compress the springand thereby apply a variable pressure to the bearing block sufiicient tohold the valve gas tight in its seat.

5. The combination in an internal combustion engine, of a valve casingprovided with port openings in its seat, a valve fitted within saidcasing and provided with connecting ports adapted to open and close theport openings in proper sequence and finished to a gas tight fit in itsseat of sufficient Width to seal the ports from leakage While inoperative communication With the cylinder, a bearing block having itsinner face closely fitted to substantially the entire effective outersurface of the valve, and means for applying a variable pressure to thebearing block just sufiicient to hold the valve gas tight in its seat.

6. The combination in an internal combustion engine of a cylindricalvalve casing fitted with port openings in its seat, a cylindrical valvefitted within said casing and provided with connecting ports adapted toopen and close the port openings in proper sequence and finished to agas tight fit in its seat of suflicient width to seal the ports fromleakage while in operative communication with the cylinder, a bearingblock having its inner face closely fitted to substantially the entireeffective outer bearing surface of the valve, and means for applying avariable pressure to the bearing block just sufficient to hold the valvegas tight in its seat.

7. The combination in aninternal combustion engine of a cylindricalvalve casing provided with a central cylinder port and an inlet andexhaust port axially disposed at opposite ends of the cylinder port, acyneeaeeo lindrical valve within said casing provided with suitablerecessed connecting ports adapted to connect the cylinder portalternately with the inlet and exhaust ports in proper sequence, a gastight seat in the valve casing ground to exact curvature of the valveand of suflicient width to seal the recessed ports against leakage whilein operative communication With the cylinder, and means for applying avariable pressure to the valve just siiflicient to hold it gas tight inits seat.

8. The combination in an internal combustion engine of a cylindricalvalve casing provided with suitable port openings therein, a cylindricalvalve within said casing having connecting ports and finished to a gastight fit on its seat Where the port openings are located of sufficientwidth to seal the connecting ports against leakage while in operativecommunication with the cylinder, a bearing block having an efi'ectivearea in contact with the valve substantially equal to that of itsfinished seat and located opposite thereto, a pressure block having anarea. somewhat greater than the area of the cylinder port secured to thebearing block and with its outer face in operative communication withthe gaseous pressure within the combustion chamber, and means for movingsaid valve to cause the opening and closing of the ports in propersequence.

9. The combinaion in an internal combustion engine of a cylindricalvalve casing provided with a centrally located cylinder port with aninlet port and an exhaust port axially disposed at opposite ends of thecylinder port, a cylindrical valve within said casing having suitablerecessed connecting ports, adapted to connect the inlet and exhaustports alternately in proper sequence 3 valve gas tight in its seat.

10. The combination in an internal combustion engine of 'a cylindricalvalve casing provided with a centrally located cylinder port with aninlet port and an exhaust port, v

axially disposed at each end of the cylinder port, a cylindrical valvewithin said casing having suitable recessed connecting ports adapted toconnect the inlet and exhaust ports alternately in proper sequence withthe central cylinder port, a gas tight seat in the valve casing groundto the exact curvature of the valve and of suflicient width to seal thevalve ports against leakage while in operative communication with thecylinder, a pressure chamber in open communication with the combustionchamber and provided with a flexible gas tight diaphragm, and a bearingblock having its inner face closely fitted to substantially the entireeffective bearing surface of the valve and the minimum area of its outerface sufiicient to hold the valve gas tight in its seat being in directcontact with the flexible diaphragm.

11. The combination in an internal combustion engine of a cylindricalvalve casing provided with a centrally located cylinder port with aninlet port and an exhaust port axially disposed at each end of thecylinder port, a cylindrical valve within said casing having suitablerecessed connecting ports adapted to connect the inlet and exhaust portsalternately in proper sequence with the central cylinder port, a bearingblock closely fitted to the surface of the valve with an areasubstantially equal to the effective bearing surface of said valve, apressure block with an area somewhat greater than that of the cylinderport connected to the outer face of the bearing block, a frame plateclosely fitting the pressure block and spaced from contact with thebearing block, a flexible gas tight diaphragm covering the pressureblock, a recessed plate bolted to the outer face of the valve casingforming a pressure chamber substantially equal in area to the pressureblock, and an open passage between the pressure chamber and thecombustion chamber.

12. The combination in an internal combustion engine of a cylinder valvecasing, provided with a centrally located cylinder port with an inletport and an exhaust port axially disposed at each end of the cylinderport, a cylindrical valve within said casing -.of the bearing block, a

having suitable recessed connecting ports adapted to connect the inletand exhaust ports in proper sequence with the central cylinder port, agas tight seat in the valve casing ground to the exact curvature of thevalve and of suflicient width to seal the valve ports against leakagewhile, in operative communication with the cylinder, a bearing blockclosely fitted to the surface of the valve with an area substantiallyequal to the effective area of said valve, a pressure block with an areasomewhat greater than that of the cylinder port connected to the outerface frame plate closely fitting the pressure block and spaced fromcontact with the bearing block, a flexible gas tight diaphragm coveringthe pressure block, a recessed plate bolted'to the outer face of thevalve casing forming a pressure cham ber substantially equal in area tothe pressure block, and an open passage between the pressure chamber andthe combustion cham- 13. The combination in an internal combustionengine of a cylindrical valve casing parallel to the axis of the enginecylinder, a single port in said valve casing, a cylindrical valve openat each end, one end communicating with the inlet passage and the otherend communicating with the exhaust passage, port openings through thevalve walls adapted to connect the inlet and exhaust passages in propersequence with the single cylinder port, and means for rotating the valveat the required rate.

Signed at Denver, Colorado, this 16th day of September, 1913.

F ANK MoC-LINTOCK.

Witnesses:

ELLA E. MILLER, WM. Gun.

